Is Pluto a planet after all? New Horizons probe visit could offer new insights

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Although it was recently demoted to dwarf plant status, Pluto is still the most mystifying world in our solar system. But one year from now, NASA’s New Horizons spacecraft will be in prime position to plumb the depths of the planet’s mysteries.

Pluto is approximately three billion kilometers from Earth. New Horizons will pass within 10,000 kilometers of the planet on July 14, 2015. Traveling at around 43,000 kilometers per hour, the speedster is the fastest spacecraft mankind has ever created. Engineers have been working on the New Horizons mission for over a decade.

New Horizons’s extreme speed stems from the fact that it is extremely light for a spacecraft. But this advantage has a distinct trade-off. Because of its light weight, it is unable to stop, meaning that the data gathered by the craft will only represent a short timespan. However, New Horizons’s seven scientific instruments and cameras will be trained on Pluto and its largest moon Charon months before it arrives in the planet’s vicinity. The equipment will collect information about Pluto’s composition, atmosphere, and the effects of solar winds on the distant dwarf planet.

Although it was discovered by American astronomer Clyde Tombaugh in 1930 at Arizona’s Lowell Observatory, Pluto actually received its name from an 11-year-old British girl. In spite of decades of study, scientists still do not know the specific nature and composition of the planet.

Pluto was demoted in 2006 by the International Astronomical Union, and subsequently reclassified as a dwarf planet. The decision prompted an international wave of outrage. Celebrity astrophysicist Neil deGrasse Tyson, who heads the Hayden Planetarium in New York, received several angry letters condemning him for his contributions toward the “death” of Pluto. In 2000, he removed Pluto from the planetarium’s collection of planets in the solar system and instead categorized it as a member of the Kuiper Belt, an area located beyond the orbit of Neptune in which there are a number of icy worlds.